1. Field of the Invention
The present invention relates to wheel hubs and primarily bicycle type wheel hubs with clutches where the hub is free wheeling when torque is not being applied to the hub through a gear that is linked by a chain to a peddle arrangement, and will engage to transfer torque to a hub wheel when torque is applied to the peddle assembly.
2. Prior Art
Wheel hubs having clutches capable of free wheeling when a torque is not being applied thereto, as through a chain linked to a peddle arrangement, or like driving arrangement, but will engage to transmit torque to turn a hub wheel as generated by an operator turning such peddle arrangement are, of course, well known, and are in common use. For example, on bicycles that are directly driven through a single gear, or include multi-speed gearing. One such earlier hub design, that is believed to be the basic design of most earlier hubs for use with multi-speed gearing, is shown in FIGS. 1, 2A and 2B and is described as prior art in the Detailed Description portion of this application. This earlier hub, unlike the invention, is a ratchet type design that includes an annular ring gear that has its outer circumference secured to the inner wall of a hub body and includes teeth or notches formed around the ring gear inner circumference that slope in the direction of turning of the hub body when it is free wheeling, and includes pawls that are spring biased and are connected to extend outwardly at spaced intervals from around a peddle assembly that each have a tooth end. In free wheeling operations, the outwardly biased pawl tooth ends will each travel up the slope of each ring gear tooth or annular notch, and with the spring biasing to extend each pawl tooth end to cause the pawl end to travel down the tooth or annular notch face and engage the next tooth or annular notch face. Thereby, when the peddle assembly is turned, that turning will be against the slope of the ring gear teeth or annular notch, and the pawl tooth ends will engage and bind against the ring gear teeth faces or annular notches, transmitting an applied torque through the ring gear and into the wheel hub body to drive the wheel.
The above described spring-actuated ratchet type design for a hub clutch has, since the early nineteen hundreds, been the standard for over-running wheel hub transmissions. In practice, such spring-actuated ratchet type design provides a torque transfer from a peddle assembly, or the like, to turn a wheel at the expense of reliability and durability. and accordingly necessitates high-maintenance costs. This is because the hub clutch components, specifically the pawls and their springs, are exposed to high cyclical fatigue and are therefore failure prone. Such failure is characterized by cracked pawls, or broken or bent springs. Typically, in the event of a failure of only one of the springs or pawls, a typical lightweight, high performance wheel hub will suffer a rapid deterioration of the remaining spring pawl components, resulting in total hub failure.
Additionally, earlier systems as have employed ball bearing assemblies for power transfer through a hub to turn a wheel have not included a series of spaced pockets that each incorporates a sloping side configuration like that of the invention and have required that each ball bearing carry both a radial load, that is applied perpendicular to the bearing assembly, and axial loads as are transmitted through the axle. In such earlier systems, higher friction forces have resulted from a scrubbing of the bearing surface as occurs at the portion of the ball bearing that carries radial loads with the bearing portion as supports radial loads tending to rotate faster than the ball bearing portion that is carrying thrust loads. In the invention, radial loads are contained and carried at an annular race and seat portion wherein the spaced sloping pockets of the hub assembly are formed, and the hub assembly preferably includes a separate axle thrust bearing or bearings that incorporate radially spaced needle bearings to support axial loads.
Unlike earlier wheel hub designs, the hub of the invention will not deteriorate when exposed to cyclical fatigue, in that it does not include the vulnerable and unreliable spring biased pawls, but rather employs a unique combination of hub body race arrangement that is formed as spaced sloping pockets and opposing annular ring that includes spaced cup or step segments with ball bearings installed into which opposing sloping pockets and cup or step segments, providing immediate engagement upon receipt of a torque or turning force.